:root {
    --color-green: #0e6248;
    --color-green-hover: #0a4d38;
    --color-green-bright: #29ad49;
    --color-green-light: #e8f5f1;
    --color-green-muted: #5a9e82;
    --color-green-glow: rgba(14, 98, 72, 0.12);
    --color-accent: #f0371b;
    --color-dark: #1a2e28;
    --color-dark-footer: #0a2920;
    --color-bg: #f4faf7;
    --color-white: #ffffff;
    --color-text: #1a2e28;
    --color-text-muted: #6b8a7e;
    --color-text-secondary: #3d5a50;
    --color-border: #d4e8df;
    --color-error: #e92f2a;
    --radius-sm: 10px;
    --radius: 16px;
    --radius-lg: 24px;
    --shadow-sm: 0 2px 8px rgba(14, 98, 72, 0.06);
    --shadow: 0 8px 32px rgba(14, 98, 72, 0.1);
    --shadow-lg: 0 16px 48px rgba(14, 98, 72, 0.14);
    --transition: 0.25s cubic-bezier(0.4, 0, 0.2, 1);
}

*, *::before, *::after {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

html {
    font-size: 16px;
    scroll-behavior: smooth;
}

body {
    font-family: system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
    background: var(--color-bg);
    background-image:
        radial-gradient(ellipse 80% 50% at 50% -20%, rgba(41, 173, 73, 0.15), transparent),
        radial-gradient(ellipse 60% 40% at 100% 100%, rgba(14, 98, 72, 0.08), transparent);
    color: var(--color-text);
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    line-height: 1.55;
    -webkit-font-smoothing: antialiased;
}

.container {
    width: 100%;
    max-width: 760px;
    margin: 0 auto;
    padding: 0 20px;
}

/* Header */
.header {
    background: rgba(255, 255, 255, 0.85);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    padding: 16px 0;
    border-bottom: 1px solid var(--color-border);
    position: sticky;
    top: 0;
    z-index: 10;
}

.header__inner {
    display: flex;
    flex-direction: row;
    align-items: center;
    justify-content: space-between;
    gap: 16px;
}

.header__brand {
    display: flex;
    flex-direction: column;
    gap: 2px;
}

.header__logo {
    max-width: 180px;
    height: auto;
    width: auto;
}

.header__pill {
    display: none;
    background: var(--color-green-light);
    color: var(--color-green);
    font-size: 0.75rem;
    font-weight: 600;
    padding: 6px 14px;
    border-radius: 99px;
    border: 1px solid var(--color-border);
    white-space: nowrap;
}

.header__actions {
    display: flex;
    align-items: center;
    gap: 10px;
    flex-shrink: 0;
}

.lang-switcher {
    display: flex;
    align-items: center;
    gap: 2px;
}

.lang-switcher__btn {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 2px;
    background: none;
    border: 2px solid transparent;
    border-radius: 8px;
    padding: 4px 8px;
    cursor: pointer;
    opacity: 0.5;
    transition: opacity var(--transition), border-color var(--transition), background var(--transition);
}

.lang-switcher__flag {
    font-size: 1.125rem;
    line-height: 1;
}

.lang-switcher__code {
    font-size: 0.625rem;
    font-weight: 600;
    letter-spacing: 0.02em;
    color: var(--color-text-secondary);
    line-height: 1;
}

.lang-switcher__btn--active .lang-switcher__code {
    color: var(--color-green);
}

.lang-switcher__btn:hover {
    opacity: 0.85;
}

.lang-switcher__btn--active {
    opacity: 1;
    border-color: var(--color-green);
    background: var(--color-green-light);
}

html[lang="zh-CN"] body {
    font-family: system-ui, -apple-system, "PingFang SC", "Microsoft YaHei", "Segoe UI", sans-serif;
}

/* Main */
.main {
    flex: 1;
    padding: 28px 0 56px;
}

.step {
    display: none;
}

.step--active {
    display: block;
    animation: fadeUp 0.45s cubic-bezier(0.4, 0, 0.2, 1);
}

@keyframes fadeUp {
    from { opacity: 0; transform: translateY(16px); }
    to { opacity: 1; transform: translateY(0); }
}

.hero-badge {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    background: var(--color-green-light);
    color: var(--color-green);
    font-size: 0.8125rem;
    font-weight: 600;
    padding: 8px 16px;
    border-radius: 99px;
    margin: 0 auto 20px;
    border: 1px solid var(--color-border);
}

.hero-badge::before {
    content: "";
    width: 8px;
    height: 8px;
    background: var(--color-green-bright);
    border-radius: 50%;
    animation: pulse 2s ease infinite;
}

@keyframes pulse {
    0%, 100% { opacity: 1; transform: scale(1); }
    50% { opacity: 0.6; transform: scale(0.85); }
}

.step-head {
    text-align: center;
    margin-bottom: 32px;
}

.title {
    font-size: clamp(1.375rem, 4vw, 1.875rem);
    font-weight: 700;
    color: var(--color-dark);
    letter-spacing: -0.02em;
    margin-bottom: 10px;
    line-height: 1.25;
}

.subtitle {
    font-size: 1rem;
    color: var(--color-text-muted);
    max-width: 480px;
    margin: 0 auto;
}

/* Direction cards */
.direction-cards {
    display: flex;
    flex-direction: column;
    gap: 14px;
}

.direction-card {
    background: var(--color-white);
    border: 1.5px solid var(--color-border);
    border-radius: var(--radius);
    padding: 24px 24px 24px 28px;
    cursor: pointer;
    text-align: left;
    transition:
        border-color var(--transition),
        box-shadow var(--transition),
        transform var(--transition);
    position: relative;
    width: 100%;
    font-family: inherit;
    overflow: hidden;
    box-shadow: var(--shadow-sm);
}

.direction-card::before {
    content: "";
    position: absolute;
    left: 0;
    top: 0;
    bottom: 0;
    width: 4px;
    background: var(--color-green-bright);
    border-radius: 4px 0 0 4px;
    transition: width var(--transition), background var(--transition);
}

.direction-card--b2b::before {
    background: var(--color-green);
}

.direction-card:hover,
.direction-card:focus-visible {
    border-color: var(--color-green-muted);
    box-shadow: var(--shadow-lg);
    transform: translateY(-3px);
    outline: none;
}

.direction-card:hover::before,
.direction-card:focus-visible::before {
    width: 6px;
}

.direction-card__top {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-bottom: 14px;
}

.direction-card__badge {
    display: inline-flex;
    align-items: center;
    background: linear-gradient(135deg, var(--color-green-bright), var(--color-green));
    color: var(--color-white);
    font-size: 1.0625rem;
    font-weight: 700;
    padding: 9px 20px;
    border-radius: 99px;
    letter-spacing: 0.08em;
}

.direction-card__badge--b2b {
    background: linear-gradient(135deg, var(--color-green), var(--color-green-hover));
}

.direction-card__icon {
    width: 44px;
    height: 44px;
    background: var(--color-green-light);
    border-radius: 12px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.25rem;
    flex-shrink: 0;
}

.direction-card__title {
    font-size: 1.125rem;
    font-weight: 700;
    color: var(--color-dark);
    margin-bottom: 8px;
    line-height: 1.35;
    letter-spacing: -0.01em;
}

.direction-card__desc {
    font-size: 0.875rem;
    color: var(--color-text-muted);
    line-height: 1.5;
    padding-right: 32px;
}

.direction-card__arrow {
    position: absolute;
    right: 22px;
    bottom: 24px;
    width: 36px;
    height: 36px;
    background: var(--color-green-light);
    color: var(--color-green);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.125rem;
    font-weight: 700;
    transition: background var(--transition), color var(--transition), transform var(--transition);
}

.direction-card:hover .direction-card__arrow {
    background: var(--color-green);
    color: var(--color-white);
    transform: translateX(3px);
}

/* Back button */
.back-btn {
    background: var(--color-white);
    border: 1.5px solid var(--color-border);
    color: var(--color-text-secondary);
    font-size: 0.875rem;
    font-weight: 600;
    cursor: pointer;
    padding: 10px 16px;
    margin-bottom: 24px;
    font-family: inherit;
    display: inline-flex;
    align-items: center;
    gap: 6px;
    border-radius: 99px;
    transition: border-color var(--transition), color var(--transition), background var(--transition);
}

.back-btn:hover {
    color: var(--color-green);
    border-color: var(--color-green-muted);
    background: var(--color-green-light);
}

/* Form */
.form {
    background: var(--color-white);
    border-radius: var(--radius-lg);
    padding: 32px 24px;
    box-shadow: var(--shadow);
    border: 1px solid var(--color-border);
}

.form__grid {
    display: flex;
    flex-direction: column;
    gap: 18px;
    margin-bottom: 28px;
}

.form__group {
    display: flex;
    flex-direction: column;
    gap: 7px;
}

.form__label {
    font-size: 0.8125rem;
    font-weight: 600;
    color: var(--color-text-secondary);
    text-transform: uppercase;
    letter-spacing: 0.04em;
}

.required {
    color: var(--color-green);
}

.optional {
    font-weight: 400;
    color: var(--color-text-muted);
    text-transform: none;
    letter-spacing: 0;
    margin-left: 0.35em;
}

.form__input {
    border: 1.5px solid var(--color-border);
    border-radius: var(--radius-sm);
    padding: 14px 16px;
    font-size: 1rem;
    font-family: inherit;
    color: var(--color-text);
    background: var(--color-bg);
    transition: border-color var(--transition), box-shadow var(--transition), background var(--transition);
    width: 100%;
    -webkit-appearance: none;
}

.form__input::placeholder {
    color: var(--color-text-muted);
    opacity: 0.7;
}

.form__input:focus {
    outline: none;
    border-color: var(--color-green);
    background: var(--color-white);
    box-shadow: 0 0 0 4px var(--color-green-glow);
}

.form__input:invalid:not(:placeholder-shown) {
    border-color: var(--color-error);
}

.form__input--error {
    border-color: var(--color-error);
    background: var(--color-white);
    box-shadow: 0 0 0 4px rgba(233, 47, 42, 0.12);
}

.form__input--error:focus {
    border-color: var(--color-error);
    box-shadow: 0 0 0 4px rgba(233, 47, 42, 0.12);
}

.form__interests--error .interests-grid {
    outline: 1.5px solid var(--color-error);
    outline-offset: 4px;
    border-radius: var(--radius-sm);
}

.form__consent--error {
    border-color: var(--color-error);
    background: rgba(233, 47, 42, 0.04);
}

.form__interests {
    border: none;
    margin-bottom: 24px;
}

.form__interests .form__label {
    margin-bottom: 14px;
}

.interests-grid {
    display: flex;
    flex-direction: column;
    gap: 8px;
}

.interest-item {
    display: flex;
    align-items: flex-start;
    gap: 12px;
    cursor: pointer;
    padding: 14px 16px;
    border: 1.5px solid var(--color-border);
    border-radius: var(--radius-sm);
    background: var(--color-bg);
    transition: border-color var(--transition), background var(--transition), box-shadow var(--transition);
}

.interest-item:hover {
    border-color: var(--color-green-muted);
    background: var(--color-green-light);
}

.interest-item:has(input:checked) {
    border-color: var(--color-green);
    background: var(--color-green-light);
    box-shadow: 0 0 0 3px var(--color-green-glow);
}

.interest-item input[type="checkbox"] {
    width: 20px;
    height: 20px;
    margin-top: 1px;
    flex-shrink: 0;
    accent-color: var(--color-green);
    cursor: pointer;
}

.interest-item span {
    font-size: 0.9375rem;
    line-height: 1.45;
    color: var(--color-text);
}

.form__consent {
    display: flex;
    align-items: flex-start;
    gap: 12px;
    font-size: 0.8125rem;
    color: var(--color-text-muted);
    margin-bottom: 24px;
    cursor: pointer;
    padding: 14px 16px;
    background: var(--color-green-light);
    border-radius: var(--radius-sm);
    border: 1px solid var(--color-border);
}

.form__consent input[type="checkbox"] {
    width: 20px;
    height: 20px;
    margin-top: 1px;
    flex-shrink: 0;
    accent-color: var(--color-green);
}

.form__consent a {
    color: var(--color-green);
    font-weight: 600;
    text-decoration: underline;
    text-underline-offset: 2px;
}

.form__field-error {
    margin: 6px 0 0;
    min-height: 0;
    font-size: 0.8125rem;
    line-height: 1.4;
    color: var(--color-error);
}

.form__field-error[hidden] {
    display: none;
}

.form__error {
    background: #fff5f5;
    border: 1px solid #ffd5d5;
    color: var(--color-error);
    border-radius: var(--radius-sm);
    padding: 14px 16px;
    font-size: 0.875rem;
    margin-bottom: 16px;
}

.honeypot {
    position: absolute;
    left: -9999px;
    opacity: 0;
    height: 0;
    width: 0;
    overflow: hidden;
}

/* Buttons */
.btn {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    width: 100%;
    padding: 16px 28px;
    border: none;
    border-radius: 99px;
    font-size: 1rem;
    font-weight: 700;
    font-family: inherit;
    cursor: pointer;
    letter-spacing: 0.01em;
    transition:
        background var(--transition),
        transform var(--transition),
        box-shadow var(--transition);
}

.btn--primary {
    background: linear-gradient(135deg, var(--color-green-bright) 0%, var(--color-green) 100%);
    color: var(--color-white);
    box-shadow: 0 4px 16px rgba(14, 98, 72, 0.35);
}

.btn--primary:hover:not(:disabled) {
    background: linear-gradient(135deg, var(--color-green) 0%, var(--color-green-hover) 100%);
    box-shadow: 0 6px 24px rgba(14, 98, 72, 0.45);
    transform: translateY(-1px);
}

.btn--primary:active:not(:disabled) {
    transform: translateY(0);
}

.btn--primary:disabled {
    opacity: 0.65;
    cursor: not-allowed;
}

.btn--secondary {
    background: var(--color-white);
    color: var(--color-green);
    border: 2px solid var(--color-green);
    max-width: 340px;
    margin: 0 auto;
    box-shadow: none;
}

.btn--secondary:hover {
    background: var(--color-green-light);
    transform: translateY(-1px);
}

.btn__loader {
    width: 20px;
    height: 20px;
    border: 2px solid rgba(255, 255, 255, 0.35);
    border-top-color: white;
    border-radius: 50%;
    animation: spin 0.7s linear infinite;
}

@keyframes spin {
    to { transform: rotate(360deg); }
}

/* Success */
.success {
    text-align: center;
    padding: 56px 28px;
    background: var(--color-white);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow);
    border: 1px solid var(--color-border);
}

.success__icon {
    width: 80px;
    height: 80px;
    background: linear-gradient(135deg, var(--color-green-bright), var(--color-green));
    color: white;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 2.25rem;
    font-weight: 700;
    margin: 0 auto 28px;
    box-shadow: 0 8px 24px rgba(41, 173, 73, 0.35);
}

.success .subtitle {
    margin-bottom: 28px;
}

/* Footer */
.footer {
    background: linear-gradient(180deg, var(--color-dark-footer) 0%, #061a14 100%);
    padding: 28px 0;
    margin-top: auto;
    border-top: 3px solid var(--color-green-bright);
}

.footer__inner {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 8px;
    text-align: center;
}

.footer p,
.footer a {
    font-size: 0.8125rem;
    color: rgba(255, 255, 255, 0.65);
}

.footer a {
    text-decoration: none;
    color: var(--color-green-bright);
    font-weight: 600;
    transition: color var(--transition);
}

.footer a:hover {
    color: #5fd47a;
}

/* Tablet+ */
@media (min-width: 600px) {
    .header__pill {
        display: block;
    }

    .header__actions {
        gap: 14px;
    }

    .lang-switcher__btn {
        padding: 5px 8px;
    }

    .lang-switcher__flag {
        font-size: 1.25rem;
    }

    .lang-switcher__code {
        font-size: 0.6875rem;
    }

    .direction-cards {
        flex-direction: row;
        gap: 16px;
    }

    .direction-card {
        flex: 1;
        display: flex;
        flex-direction: column;
    }

    .direction-card__desc {
        flex: 1;
        padding-right: 0;
    }

    .direction-card__arrow {
        position: static;
        margin-top: 20px;
        align-self: flex-start;
    }

    .form {
        padding: 36px 32px;
    }

    .form__grid {
        display: grid;
        grid-template-columns: 1fr 1fr;
    }

    .form__group:first-child,
    .form__group:nth-child(2) {
        grid-column: span 1;
    }

    .interests-grid {
        display: grid;
        grid-template-columns: 1fr 1fr;
        gap: 10px;
    }
}

@media (min-width: 900px) {
    .container {
        max-width: 820px;
    }
}