/* ============================================================
   Student Login Page  — TBS Exchange Application
   ไฟล์นี้แยกเฉพาะหน้า Login (โหลดผ่าน @section Styles)
   ============================================================ */

:root {
    --login-primary: #1e3a8a;      /* navy */
    --login-primary-dark: #172554;
    --login-accent: #c8a04b;       /* gold */
    --login-accent-dark: #a9843a;
    --login-danger: #dc2626;
    --login-text: #1f2937;
    --login-muted: #6b7280;
    --login-border: #e2e8f0;
    --login-bg: #f1f5f9;
    --login-radius: 16px;
    --login-shadow: 0 20px 45px rgba(15, 23, 42, 0.18);
}

/* พื้นหลังทั้งหน้า */
.login-page {
    min-height: calc(100vh - 160px);
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 48px 16px;
    background: radial-gradient(circle at top left, #e0e7ff 0, transparent 45%),
                radial-gradient(circle at bottom right, #fef3c7 0, transparent 40%),
                var(--login-bg);
}

/* การ์ดหลัก แบ่งซ้าย-ขวา */
.login-card {
    width: 100%;
    max-width: 900px;
    display: grid;
    grid-template-columns: 1.05fr 1fr;
    background: #ffffff;
    border-radius: var(--login-radius);
    box-shadow: var(--login-shadow);
    overflow: hidden;
}

/* ---- ฝั่งซ้าย : แบรนด์ ---- */
.login-brand {
    position: relative;
    padding: 48px 40px;
    color: #fff;
    background: linear-gradient(150deg, var(--login-primary) 0%, var(--login-primary-dark) 100%);
    display: flex;
    flex-direction: column;
    justify-content: space-between;
    overflow: hidden;
}

.login-brand::after {
    content: "";
    position: absolute;
    right: -70px;
    bottom: -70px;
    width: 220px;
    height: 220px;
    border-radius: 50%;
   /* background: rgba(200, 160, 75, 0.18);*/
}

.login-brand::before {
    content: "";
    position: absolute;
    right: 40px;
    top: -60px;
    width: 140px;
    height: 140px;
    border-radius: 50%;
   /* background: rgba(255, 255, 255, 0.06);*/
}

.login-brand__logo {
    height: 54px;
    width: auto;
    margin-bottom: 32px;
    filter: brightness(0) invert(1);
    position: relative;
    z-index: 1;
}

.login-brand__title {
    font-size: 1.9rem;
    font-weight: 700;
    line-height: 1.25;
    margin: 0 0 12px;
    position: relative;
    z-index: 1;
}

.login-brand__subtitle {
    font-size: 1rem;
    color: rgba(255, 255, 255, 0.82);
    margin: 0;
    position: relative;
    z-index: 1;
}

.login-brand__year {
    display: inline-block;
    margin-top: 20px;
    padding: 6px 14px;
    font-size: 0.85rem;
    font-weight: 500;
    border-radius: 999px;
    background: rgba(255, 255, 255, 0.14);
    border: 1px solid rgba(255, 255, 255, 0.25);
    position: relative;
    z-index: 1;
}

.login-brand__note {
    position: relative;
    z-index: 1;
    font-size: 0.86rem;
    color: rgba(255, 255, 255, 0.72);
    line-height: 1.6;
    margin: 28px 0 0;
    padding-top: 20px;
    border-top: 1px solid rgba(255, 255, 255, 0.16);
}

/* ---- ฝั่งขวา : ฟอร์ม ---- */
.login-form-wrap {
    padding: 48px 44px;
    display: flex;
    flex-direction: column;
    justify-content: center;
}

.login-form-wrap h2 {
    font-size: 1.6rem;
    font-weight: 700;
    color: var(--login-text);
    margin: 0 0 6px;
}

.login-form-wrap .login-lead {
    font-size: 0.95rem;
    color: var(--login-muted);
    margin: 0 0 28px;
}

.login-field {
    margin-bottom: 20px;
}

.login-field label {
    display: block;
    font-size: 0.88rem;
    font-weight: 600;
    color: var(--login-text);
    margin-bottom: 8px;
}

.login-input-group {
    display: flex;
    align-items: center;
    border: 1.5px solid var(--login-border);
    border-radius: 10px;
    background: #f8fafc;
    transition: border-color .15s ease, box-shadow .15s ease, background .15s ease;
}

.login-input-group:focus-within {
    border-color: var(--login-primary);
    background: #fff;
    box-shadow: 0 0 0 4px rgba(30, 58, 138, 0.10);
}

.login-input-group i {
    padding: 0 12px;
    color: var(--login-muted);
    font-size: 1.05rem;
}

.login-input-group input {
    flex: 1;
    border: 0;
    outline: 0;
    background: transparent;
    padding: 13px 12px 13px 0;
    font-size: 0.98rem;
    color: var(--login-text);
    min-width: 0;
}

/* suffix @tbs.tu.ac.th */
.login-input-suffix {
    padding: 0 14px;
    font-size: 0.85rem;
    color: var(--login-muted);
    white-space: nowrap;
    border-left: 1px solid var(--login-border);
    align-self: stretch;
    display: flex;
    align-items: center;
    background: #eef2f7;
    border-radius: 0 8px 8px 0;
}

.login-field .login-hint {
    font-size: 0.8rem;
    color: var(--login-muted);
    margin: 8px 2px 0;
}

/* ปุ่มโชว์/ซ่อนรหัส */
.login-toggle-pass {
    border: 0;
    background: transparent;
    color: var(--login-muted);
    cursor: pointer;
    padding: 0 14px;
    font-size: 1.05rem;
}

.login-toggle-pass:hover {
    color: var(--login-primary);
}

/* ปุ่มเข้าสู่ระบบ */
.login-btn {
    width: 100%;
    border: 0;
    border-radius: 10px;
    padding: 14px 18px;
    font-size: 1.02rem;
    font-weight: 600;
    color: #fff;
    background: linear-gradient(135deg, var(--login-primary) 0%, var(--login-primary-dark) 100%);
    cursor: pointer;
    transition: transform .12s ease, box-shadow .12s ease, opacity .12s ease;
    box-shadow: 0 10px 20px rgba(30, 58, 138, 0.25);
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 10px;
    margin-top: 6px;
}

.login-btn:hover:not(:disabled) {
    transform: translateY(-1px);
    box-shadow: 0 14px 26px rgba(30, 58, 138, 0.32);
}

.login-btn:disabled {
    opacity: 0.7;
    cursor: not-allowed;
    transform: none;
}

/* spinner เล็กในปุ่ม */
.login-btn__spinner {
    width: 18px;
    height: 18px;
    border: 2.5px solid rgba(255, 255, 255, 0.45);
    border-top-color: #fff;
    border-radius: 50%;
    animation: login-spin 0.7s linear infinite;
    display: none;
}

.login-btn.is-loading .login-btn__spinner {
    display: inline-block;
}

.login-btn.is-loading .login-btn__label {
    opacity: 0.85;
}

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

/* กล่อง error */
.login-alert {
    display: flex;
    align-items: flex-start;
    gap: 10px;
    background: #fef2f2;
    border: 1px solid #fecaca;
    color: #991b1b;
    border-radius: 10px;
    padding: 12px 14px;
    font-size: 0.9rem;
    margin-bottom: 22px;
}

.login-alert i {
    font-size: 1.05rem;
    margin-top: 1px;
}

/* ลิงก์ย้อนกลับ */
.login-back {
    text-align: center;
    margin-top: 22px;
    font-size: 0.88rem;
    color: var(--login-muted);
}

.login-back a {
    color: var(--login-primary);
    font-weight: 600;
    text-decoration: none;
}

.login-back a:hover {
    text-decoration: underline;
}

/* ---- Loading overlay (กันกดเบิ้ล) ---- */
.login-overlay {
    position: fixed;
    inset: 0;
    background: rgba(15, 23, 42, 0.55);
    backdrop-filter: blur(2px);
    display: none;
    align-items: center;
    justify-content: center;
    flex-direction: column;
    z-index: 1080;
}

.login-overlay.show {
    display: flex;
}

.login-overlay__spinner {
    width: 56px;
    height: 56px;
    border: 5px solid rgba(255, 255, 255, 0.3);
    border-top-color: var(--login-accent);
    border-radius: 50%;
    animation: login-spin 0.8s linear infinite;
}

.login-overlay__text {
    color: #fff;
    margin-top: 18px;
    font-size: 1.05rem;
    letter-spacing: .3px;
}

/* ---- Responsive ---- */
@media (max-width: 768px) {
    .login-card {
        grid-template-columns: 1fr;
        max-width: 460px;
    }

    .login-brand {
        padding: 36px 32px;
    }

    .login-brand__note {
        display: none;
    }

    .login-form-wrap {
        padding: 36px 28px;
    }
}